Pga gene from the industrial strain off. coli RE3 hyperproducing penicillin G acylase (PGA) was cloned using a simple and rapid NIPAB-based chromogenic method for the. detection of PGA-positive recombinant clones. Heterogeneous genetical material was prepared by subcloning pga in vectors pACYC184, pBR322-2 and pK19. The highest constitutive expression of pga was observed in a strain bearing the recombinant plasmid pKA18 synthesizing 2.5 times more of enzyme than the parent strain.